Employee Benefit Plans - Estimated Benefit Payments (Detail) $ in Thousands	Dec. 31, 2022 USD ($)
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2023	$ 1,698
2024	1,684
2025	1,640
2026	1,604
2027	1,575
2028 - 2032	7,215
Pension Benefits \| Summit Materials, LLC
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2023	1,698
2024	1,684
2025	1,640
2026	1,604
2027	1,575
2028 - 2032	7,215
Healthcare & Life Ins
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2023	484
2024	496
2025	515
2026	531
2027	555
2028 - 2032	2,560
Healthcare & Life Ins \| Summit Materials, LLC
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2023	484
2024	496
2025	515
2026	531
2027	555
2028 - 2032	$ 2,560

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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